One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,5,4)(3,6,8,7)(10,13)(14,15)(18,22)(19,23)(26,30)(27,33)(28,36)(38,40)(1,3,5,8)(2,6,4,7)(9,10)(11,14)(12,13)(15,16)(17,18,21,22)(19,24,23,20)(26,30)(28,36)(31,34)(35,39)(2,4)(6,7)(9,10,12,13)(11,15,16,14)(17,19,21,23)(18,20,22,24)(25,26)(27,34)(28,32)(29,30)(31,33)(35,40)(36,37)(38,39)(1,4,5,2)(3,7,8,6)(9,10)(11,14)(12,13)(15,16)(17,20)(18,19)(21,24)(22,23)(25,27,29,33)(26,31,30,34)(28,35,36,39)(32,38,37,40)(1,3)(2,6)(4,7)(5,8)(9,11)(10,14)(12,16)(13,15)(17,20)(18,19)(21,24)(22,23)(25,28,29,36)(26,32,30,37)(27,35,33,39)(31,38,34,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.